• 융합신호처리학회논문지
• /
• 제16권2호
• /
• pp.35-39
• /
• 2015

Auditory and visual stimuli presented in the peripheral visual field were perceived as spatially coincident when the auditory stimulus was presented five to seven degrees outwards from the direction of the visual stimulus. Furthermore, judgments of the perceived distance between auditory and visual stimuli presented in the periphery did not increase when an auditory stimulus was presented in the peripheral side of the visual stimulus. As to the origin of this phenomenon, there would seem to be two possibilities. One is that the participants could not perceptually distinguish the distance on the peripheral side because of the limitation of accuracy perception. The other is that the participants could distinguish the distances, but could not evaluate them because of the insufficient experimental setup of auditory stimuli. In order to confirm which of these two alternative explanations is valid, we conducted an experiment similar to that of our previous study using a sufficient number of loudspeakers for the presentation of auditory stimuli. Results revealed that judgments of perceived distance increased on the peripheral side. This indicates that we can perceive discrimination between audio and visual stimuli on the peripheral side.

• 말소리와 음성과학
• /
• 제9권4호
• /
• pp.123-128
• /
• 2017

This study aims to compare the performance of syllable identification task according to auditory and visual stimuli presentation methods and syllable position. Twenty-two typically developing children (age 4-6) participated in the study. Three-syllable words were used to identify the first syllable and the final syllable in each word with auditory and visual stimuli. For the auditory stimuli presentation, the researcher presented the test word only with oral speech. For the visual stimuli presentation, the test words were presented as a picture, and asked each child to choose appropriate pictures for the task. The results showed that when tasks were presented visually, the performances of phonological awareness were significantly higher than in presenting with auditory stimuli. Also, the performances of the first syllable identification were significantly higher than those of the last syllable identification. When phonological awareness task are presented by auditory stimuli, it is necessary to go through all the steps of the speech production process. Therefore, the phonological awareness performance by auditory stimuli may be low due to the weakness of the other stages in the speech production process. When phonological awareness tasks are presented using visual picture stimuli, it can be performed directly at the phonological representation stage without going through the peripheral auditory processing, phonological recognition, and motor programming. This study suggests that phonological awareness skills can be different depending on the methods of stimulus presentation and syllable position of the tasks. The comparison of performances between visual and auditory stimulus tasks will help identify where children may show weakness and vulnerability in speech production process.

• Investigative Magnetic Resonance Imaging
• /
• 제9권1호
• /
• pp.24-29
• /
• 2005

목적 : 기존의 시각 자극과 관련한 뇌기능 연구가 일반적인 이차원 시각 자극을 이용한 데 반하여 본 논문에서는 삼차원 스트레오스코픽 비젼에 의한 시각 자극을 이용한 뇌기능 영상 연구를 수행하였다. 본 연구를 통하여 삼차원 시각처리와 관련한 뇌의 기능 영역 및 특징을 이차원 시각 자극 결과와 비교 검토하였다. 대상 및 방법 Anaglyph(이차원 그림을 칼라 코딩한 후 왼쪽과 오른쪽에 서로 다른 색깔의 렌즈를 사용하여 스트레오스코픽 비젼을 구현)를 이용하여 삼차원 시각 자극을 주었으며, 이와 비교를 위하여 동일한 영상으로 이차원 시각 자극을 구현하였다. 건강한 volunteer들에 대하여 삼차원 및 이차원 시각 자극에 대한 뇌기능 영상을 3.0 Tesla MRI 시스템에서 얻었다. 결과 : 삼차원 시각 자극에 의하여 활성화된 뇌의 영역은 이차원 시각 자극과 동일하게 후두엽으로 나타났으며, 삼차원 시각 자극에 의한 활성영역이 이차원 시각 자극에 의한 영역 보다 약 $18\%$ 더 넓게 나타났다. 결론 : 사람은 양 눈을 사용하여 삼차원 물체를 인식한다. 삼차원 물체 인식은 스테레오스코픽 비젼에 기인하는데, anaglyph 를 이용하여 삼차원 시각 자극에 대한 뇌기능 영상을 3.0 Tesla MRI 시스템에서 수행하였다. 삼차원 시각 자극에 의하여 활성화된 뇌의 영역은 이차원 시각 자극과 동일하게 후두엽으로 나타났으나, 활성영역이 이차원 자극에 비하여 약 $18\%$ 더 넓게 나타났다. 이것은 삼차원 영상 처리가 이차원 영상 처리에 비하여 왼쪽 영상과 오른쪽 영상의 차이에서 거리 정보를 추출하는 삼차원 시각 처리 기능이 추가됨에 따라 뇌의 처리 영역이 넓어진 것으로 판단된다. 이러한 삼차원 시각 자극 뇌기능 영상은 가상현실이나 3-D 디스플레이, 3-D 멀티미디어 콘텐츠 연구 등 다양한 분야에 활용될 수 있을 것으로 기대한다.

• 대한의용생체공학회:의공학회지
• /
• 제39권2호
• /
• pp.94-102
• /
• 2018

It is known that gamma-band activity (GBA) and phase synchrony (GBPS) are induced by emotional visual stimuli. However, the characteristics of GBA and GBPS according to different emotional states have not been identified. The purpose of this study is to investigate the changes in gamma-band neuronal synchronization induced by positive and negative emotional visual stimuli using electroencephalograms (EEGs). Thirteen healthy male subjects have participated in the experiment. The induced spectral power in gamma-band was the highest for negative stimuli, and the lowest for neutral stimuli in 300-2,000 ms after the stimulus onset. The inter-regional phase synchronization in gamma-band was increased in 500-2,000 ms, mainly between the bilateral frontal regions and the parieto-occipital regions. Larger number of significant connections were found by negative stimuli compared to positive ones. Judging from temporal and spatial characteristics of the gamma-band activity and phase synchrony increases, the results may imply that affective visual stimuli cause stronger memory encoding than non-emotional stimuli, and this effect is more significant for negative emotional stimuli than positive ones.

• 대한물리치료과학회지
• /
• 제9권1호
• /
• pp.1-8
• /
• 2002

This study set out to investigate what kind of effects the consistent visual stimuli and verbal and non verbal auditory stimuli have on pain alleviation, as well as to see the influence of joint application of visual and auditory stimuli at the same time on pain alleviation, according to lightness of 50lux and 200lux, ultimately providing basic data in setting up an environment in case of treating pain. The subject were comprised of 30 male and female adults with pain in the neck and back area. The subject were treated in their pain area with Transcutaneous Electrical Nerve Stimulator(TENS) 100HZ for 20 minutes in the research set where each visual, auditory, and joint visual and auditory stimuli was given. For analysis methods, Visual Analogue Scale(VAS) and McGill Pain Questionnaire were adopted to see the changes before and after treatment, and the electrocardiogram, systolic and diastolic pressure, number of heart rate and breathing frequence and endorphin were compared and analyzed using the Wilcoxon singed-rank test. And The Kreskal-walllis test was used to compare the two subgroups from each group. Wilcoxon singed-rank test and the Kreskal-walllis test was used to compare the two subgroups from each group. The results were as follows: 1. The group of 50lux and 200lux were compared given varying degrees of visual stimuli. The group of 200lux showed more reduction in pain points, average systolic and diastolic pressure and average endorphin. 2. The group of verbal and non verbal were compared given varying degrees of auditory stimuli. The group of non-verbal showed more reduction in average systolic and diastolic pressure. 3. The group of 200lux+verbal and 200lux+non verbal were compared given varying degrees of joint visual and auditory stimuli. There was found a statistical significance(p<0.05) in endorphin between the two groups, with more endorphin reduction for 200lux+non verbal group. And there was a statistically significant reduction in VAS and McGill before and after the treatment between the two groups.

• 감성과학
• /
• 제13권3호
• /
• pp.475-484
• /
• 2010

본 연구는 의미적 속성을 가진 시각과 청각자극 간의 SOA(stimulus onset asynchrony)가 시청각 통합 현상에 미치는 영향을 살펴보고자 하였다. 시청각 통합 현상 중 표적을 의미하는 자극의 양상이 두 개 이상인 경우 표적에 반응이 빠르고 정확한 중복 표적 효과(redundant target effect)와 청각 자극에 비해 시각 자극에 대한 반응이 빠르고 정확한 시각 우세성 효과(visual dominance effect)를 중심으로 살펴보기 위해서 시각과 청각 단일 양상 표적 조건과 다중 양상 표적 조건을 구성하여 조건들의 반응시간과 정확률을 살펴보았다. 그 결과, 시 청각자극의 SOA가 변하더라도 중복 표적 효과는 이에 영향을 받지 않는 것으로 나타났으며, 두 자극 간의 SOA가 100ms 이상인 조건에서는 청각자극의 우세현상이 나타났다. 이러한 결과는 중복 표적 효과의 경우 두 양상자극 간의 SOA가 변하더라도 안정적으로 지속된다는 점을 시사하며, 청각자극의 경우 시각자극에 비해 약 100ms 이상의 시간적 이득조건이 마련되었을 때에 비로소 우세한 정보처리의 행동결과가 도출될 수 있음을 시사한다.

• 대한인간공학회지
• /
• 제30권1호
• /
• pp.195-202
• /
• 2011

Objective: The aim of this study is to investigate and review the previous researches about objective measuring fatigue caused by visual stimuli. Also, we analyze possibility of alternative visual fatigue measurement methods using facial expression recognition and gesture recognition. Background: In most previous researches, visual fatigue is commonly measured by survey or interview based subjective method. However, the subjective evaluation methods can be affected by individual feeling's variation or other kinds of stimuli. To solve these problems, signal and image processing based visual fatigue measurement methods have been widely researched. Method: To analyze the signal and image processing based methods, we categorized previous works into three groups such as bio-signal, brainwave, and eye image based methods. Also, the possibility of adopting facial expression or gesture recognition to measure visual fatigue is analyzed. Results: Bio-signal and brainwave based methods have problems because they can be degraded by not only visual stimuli but also the other kinds of external stimuli caused by other sense organs. In eye image based methods, using only single feature such as blink frequency or pupil size also has problem because the single feature can be easily degraded by other kinds of emotions. Conclusion: Multi-modal measurement method is required by fusing several features which are extracted from the bio-signal and image. Also, alternative method using facial expression or gesture recognition can be considered. Application: The objective visual fatigue measurement method can be applied into the fields of quantitative and comparative measurement of visual fatigue of next generation display devices in terms of human factor.

• 한국멀티미디어학회논문지
• /
• 제20권12호
• /
• pp.1856-1864
• /
• 2017

The ultimate goal of multimedia in bio-signal research is to approach multimedia contents through bio-signal. Hence it is important to interpret user's emotions by analyzing his or her bio-signals. In this paper, we construct ERP task of oddball component to analyze EEG signal between normal stimuli and fear stimuli and measure EEG during ERP task. The results from extracted ERP component show that there is a difference in N200 in visual stimuli, P300 in auditory stimuli, and N100 and P300. Moreover, there are larger changes in audiovisual stimuli, indicating that users recognize greater fear of crime when visual and auditory stimuli are simultaneously presented.

• The Journal of Korean Physical Therapy
• /
• 제26권3호
• /
• pp.191-195
• /
• 2014

Purpose: The purpose of this study is to investigate whether types of sensory-stimuli cues in terms of visual, auditory, and visuoauditory cues can be affected to motor sequential learning in healthy adults, using serial reaction time task. Methods: Twenty four healthy subjects participated in this study, who were randomly allocated into three groups, in terms of visual-stimuli (VS) group, auditory-stimuli (AS) group, and visuoauditory-stimuli (VAS) group. In SRT task, eight Arabic numbers were adopted as presentational stimulus, which were composed of three different types of presentational modules, in terms of visual, auditory, and visuoauditory stimuli. On an experiment, all subjects performed total 3 sessions relevant to each stimulus module with a pause of 10 minutes for training and pre-/post-tests. At the pre- and post-tests, reaction time and accuracy were calculated. Results: In reaction time, significant differences were founded in terms of between-subjects, within-subjects, and interaction effect for group ${\times}$ repeated factor. In accuracy, no significant differences were observed in between-group and interaction effect for groups ${\times}$ repeated factor. However, a significant main effect of within-subjects was observed. In addition, a significant difference was showed in comparison of differences of changes between the pre- and post-test only in the reaction time among three groups. Conclusion: This study suggest that short-term sequential motor training on one day induced behavioral modification, such as speed and accuracy of motor response. In addition, we found that motor training using visual-stimuli cue showed better effect of motor skill acquisition, compared to auditory and visuoauditory-stimuli cues.

• 정보처리학회논문지B
• /
• 제10B권6호
• /
• pp.639-646
• /
• 2003

본 논문은 일련의 불연속적인 도트 자극으로부터 시각적 착시현상을 추출하는 신경회로망 모델을 제시한다. 제안된 모델은 시각 정보처리 경로에서 발견되는 시각 세포들의 특성을 근거로 한다. 본 연구는 일련의 이산 도트 자극들이 개별적인 도트들로 인식하지 않고 연속적인 가상의 윤곽으로 인식하는 시각적 착시 현상을 나타내는 생리심리학 실험을 기초로 하여 도트 자극의 시각적 착시를 구현한 것으로서 실험에서는 가상 다각형 형태로 배치된 6에서 10개의 도트자극들을 사용한다. 이 실험 데이터는 Smith & Vos가 생리심리학적 실험에서 다룬 데이터와 유사하다. 제안된 모델은 이산 도트자극으로부터 연속적인 착시 윤곽을 성공적으로 추출한다.